// Check if link is not clicked so far
$result = SQL_QUERY_ESC("SELECT b.points, d.gender, d.surname, d.family, d.status, d.ref_payout
FROM "._MYSQL_PREFIX."_user_birthday AS b
-INNER JOIN "._MYSQL_PREFIX."_user_data AS d
+INNER JOIN `"._MYSQL_PREFIX."_user_data` AS d
ON b.userid=d.userid
WHERE b.userid=%s AND b.chk_value='%s' LIMIT 1",
array($uid, $chk), __FILE__, __LINE__);